Mold and process for casting materials



H. A! MYERS MOLD AND PROCESS FOR CASTING MATERIALS May 8, 1923.

Filed April 15, 1921 'llllllllwlllllll INYE NTUR Patented May 8, 1923.

UNITED STATES HUBERT A. MYiERS, OF TOLEDO, OHIO, ASSIGNOR TO THE 'HUBEBT A. MYER OF TOLEDO, OHIO, A CORPORATION OF OHIO.

PATENT-OFFICE.

\ MOLD AND PROCESS FOR CASTING MATERIALS.

To all whom it may concern:

Be it known that I, HUBERT A. MYERS, a citizen of the United States, and a resident of Toledo, in the county of Lucas and State of Ohio, have made an invention appertaining to Molds and Processes for Casting Materials; and I dofhereby declare the following to be a full, clear, and exact description of the invention, such as will enable others 1 skilled in the art to which it a-ppertains to make and use the same, reference being had to the accompanying drawings, and to the characters of reference marked thereon, which form a partof this specification.

My invention has for its object to provide a mold wherein materials that are rendered plastic or fluid by heat, and which are structurally injured by an improper rate of cooling, may be rapidly cast and yet produce the best possible structural condition within the castings. A great variety of materials-may be cast in the molds involving my invention, such as ferrous metals, brass of relatively high fusibility, and silica compounds and mixtures, such as glass. The invention is particularly valuable. in casting ferrous metals when it is desired to rapidly produce soft metal castings having a substantially uniform structure throughout. The invention particularly provides a process for easting metals having high fusibility wherein a high substantially uniform temperature of the mold is maintained by the use of a metal of low fusibility, and preferably one having a high boiling point, a high vaporizin point, and a high heat conductivity.

vA so my invention has for its object to provide a means for constantlyfeeding to the moldin that w1l protect the mold from the action of the heated metal of the castings.

To illustrate a practical application of the invention I have selected a mold containing my invention as an example of such molds 4,5 in which the process involving my invention may be conducted. The mold selected for purposes of illustration isshown vin the ac companyin drawing and together with the process wi be described hereinafter. Figure l'of the drawing illustrates a-perspective view of the mold "Fi 2 illustrates a vertical sectional view of t e mold, and Fig. 3 illustrates a transverse sectional view of the. mold,

surface of the molds a material- Application filed April 15, 1921. Serial No. 461,623.

The mold is a metal mold and formed of two parts 1 that correspond to the drag and the cope of the ordinary foundry flask.

They are formed with registering parts that i contain the molding cavity2 of the mold and the sprue hole 3 leading thereto. The registering parts may be formed of two iron plates 4, one or both of whichmay be provided with suitable recesses or ridges "according to the configuration of the article to be cast within the mold. The portions of the plates 4 that form the cavity2 are preferably of substantially uniform thickness so as to produce a uniform heat conductivity from the surface of the cavity through the plates. The cavity 2 is jacketed by chambers '5 located in the parts '1 of the mold. The chambers 5 are contained-between the plates 4 and the side walls 6-of each of the parts 1 of the mold. The "chambers 5 are thus separated from the cavity 2 by the plates or walls 4. If desired,'the plates 4 may be formed integral with the'tops 7'of the parts 1. i

The chambers are filled with a material that will maintain the walls of the cavity 2 of the mold at a high temperature, and as far as possible maintain the temperature Such a material uniform and constant. should therefore be heat conductive and preferably heat convective. A heated liquid material having boiling and vaporizin points above 300 F may be used, whic will remove by convection the excessive heat introduced into the mold with the molten material to be cast, and nevertheless will keep the surface of the cavity at a high temperature. If the heat regulating medium has a comparatively low vaporizing point the chambers may be sealed to revent the loss of the material. .A metal of ow 'fusibil-- ity may be used, ifit has comparatively high boiling and vaporizing points. I find it preferable to use lead as the medium for controlling the heat of the surfaces of. the

cavity, since ledd not only has low fusibility and high boiling and vaporizing intsf but has'a comparatively high conductivity, and

' while in themolten state it has high fluldity,

or low viscosity. The lead willbe melted by the heat of the material cast inthe mold andwillcarry away the heat of the casting while/in the mold by conduction and convection at the proper rate, and yet ma 1ntam the walls of the cavity at a high temperature for each pouring.

The material used for controlling the temperature of the walls of the cavity is poured, while in a liquid state, into the chambers 5 through openings, such as those shown at 9. The openings may be closed by suitable covers or plugs 10 to prevent entrance of thematerial to be cast into the chambers, and, if the material for controlling the temperature has a vaporizing point such that the heat to which it is subjected vaporizes it, the vapor will be retained in the charm bers by thus sealing them.

Any suitable means may be used for closing and opening the molds, such as the hinged bars 8 that are attached to the parts I 1 of the mold.

The material to be cast is poured into the cavity through the sprue hole 3, and the heat of the material will be conducted through the thin walls of the cavity to the lead, if lead is used, which will either maintain the lead in a molten condition, or will melt the lead if it is solid. ,The parts of the mold may be'separated and the casting discharged as soon as the latter has become sufiiciently solid or strong to maintain its form, or it may be permitted to remain in the mold until it has cooled throughout to the temperature of the mold. The temperature of the wall of the cavity throughout the area of the surfaces will be maintained between the melting and boiling points of the lead, it being cooled only by the heat that may be conducted through the lead, which would be the major portion of the heat, and the heat that may be conducted along the plates 4 to the exterior of the mold. The walls of the sprue hole 3 will also be maintained to near the temperature of the walls of the cavity 2, and consequently the material cast in the mold will come into immediate contact with a surface that is nearly as high in temperature as that of the cavity.

The temperature of the walls of the cavity, and that of the heat conveying medium,

may be controlled by the rate at which the pourings are made and the castings ejected. Consequently, it is possible to maintain the cavity walls at a temperature slightly above the melting point of the lead, if lead is used, or the cavity walls may becmaintained at still higher temperatures by a corresponding increase in the rapidity of the pourings.

If it is desired to raise the walls of the cavity to a high temperature, the mold may be subjected to the heat produced by the gas burners 11. This will keep the walls of the cavity and of the sprue hole, by reason of convection of the fluid, substantially at a uniform high temperature, and localization of the intense heat of the burners, so far as the walls of the cavity are concerned, will be avoided. If the intensity of the heat produced by the burners is sufiicient to cause the lead to approach its boiling point, the temperature of the walls of the cavity will be maintained substantially constant notwithstanding the rate at which the pourings are made and the castings ejected.

Where ferrous metals are cast in the molds the uniform high temperature of the molding surfaces and the uniform rate of conductivity from the casting is very desirable to prevent local crystallization or formation of white metal or cementite in the castings. Similar molds may be used for casting other materials, provided, of course, they are manipulated according to the character of the material to be cast. To produce soft iron castings the temperature of the mold should be raised and maintained at a relatively high temperature, while for casting glass it may be found desirable to heat the mold prior to the pouring, and then allow it to partially cool before discharging the article. The volume and the conductivity of the metal or other material in the chambers of the mold will permit a uniform cooling of the glass until it is sufiiciently cooled to be removed or ejected from the mold or aliowed to be passed to a suitable tempering eer.

Tn casting certain materials the walls of the cavity and the sprue hole may be surfaced or impregnated with suitable materials to form protective films or coatings to prevent adherence of the material cast in the mold to the material of;which the walls of the cavity are formed, or to modify or protect the surfaces of the castings, such as to render them smooth. When ferrous metals are cast the molding surfaces may be coated with black wash or graphite or lamp black. If it is desired, the walls of the cavity may be surfaced or impregnated with zinc. If'the walls of the cavity are formed f iron, zinc or zinc alloy may be inserted in the chambers 5 alone or together with the lead and the walls of the cavity will draw from the reservoirs of zinc formed by the chambers, by absorption and by the high temperature produced at the molding sur face of the cavity, and thus zinc and zinc oxide will be supplied to the surface, which will form a protective coat or gas film at each pouring; as well as a partial protective coating of zinc oxide that will be formed on the surface of the cavity upon the removal of the casting. If the chambers 5 are closed, and the walls of the cavity are pregnable to zinc,'the vapor pressure will coact with such absorptive power that the walls may have for the zinc, to supply the zinc to the molding surface of the cavity and the sprue hole.

This will effectively prevent adherence of the ferrous metals cast in an iron mold notwithstanding the rapidity of the castings.

It is preferable to use lead at all times because of the comparatively high boiiling point that lead has.

I claim:

1. In a mold for casting materials, the

moldliaving a chamber and a molding cavity, a wall separating the chamber and the cavity, the chamber containing a material having a boiling point above 1,000 F.

2. In a mold for casting materials, the mold having a chamber and a molding cavity, a wall separating the chamber and the cavity, the chamber containing a'metal of low fusibilityf I '3. In a mold for casting materials, the mold having a chamber and a molding cavity, a wall separating the chamber and the cavity, the chamber containing a metal of low fus'ibility, and means for heating the metal.

' mold having a chamber and a molding cavity, a wall separating the chamber and the cavity, the chamber containing lead.

7. In a mold for casting materials, the mold having a chamber located in proximity to the matrix of the mold and containing lead, means for heatin the lead.

8. In a mold for casting metals, the mold having a chamber and a molding cavity, a

. wall for separating the chamber from the cavity, the molding surface of the cavity surfaced with a metal gasifiable below the temperature of the melting point of the metal cast, and the chamber containing a metal of low fusibility..

9. In a mold for casting metals, the mold having a chamber and a molding cavity, a wall for separating the chamber from the cavity, the molding surface of the cavity surfaced with a metal gasifiable below the temperature of the. melting point of the metal cast, the chamber containing lead.

10. In a mold for casting metals, the mold having a chamber and a molding cavity, a wall for separating the chamber from the cavity, the moldin surface of the cavity surfaced with a meta gasifiable below the temperature of the melting point of the metal cast, and the chamber containin a metal of low fusibility and the said gasi able metal.

11. In a mold .for casting metals, the mold having a chamber. and a-molding cavity, a wall for separating the chamber from. the

surfaced with a metal gasifiable below the temperature of the melting point of the metal cast, the chamber containing lead and the gasifiable metal.

12. In a moldfor casting metals, the mold having a chamber and a molding cavity, a wall for separating the chamber and the cavity, the'molding surface of the cavity surfaced with zinc, and the chamber containing lead.

13. In a mold for casting metals, the mold having a chamber and a molding cavity, a wall for separating the chamber and the cavity, the molding wall of the cavity.impregnated with zinc, and the chamber containing zinc.

14. In a mold for casting metals, the mold .having'a chamber and a molding cavity. a wall for separating the chamber and the taining lead and zinc.

15. In a mold for casting metals, the mold having a molding cavity and a closed chamber, a wall for separating the chamber and the cavity. the chamber containing a metal gasifiable'below the melting point of the metal cast.

16. In a mold for casting metals, the mold having a molding ca-vityand a closed cham- 6. In a mold for casting materials, the

her, a Wall for separating the chamber and the cavity, the wall impregnatedwith a metal gasifiable below the temperature of the metal cast, and the chamber containing rounding the matrix of the mold, the chambers containing metal having low fusibility, the walls of the cavity impregnated with a metal gasifiable below the temperature of the melting point of the material cast, and the metal of low fusibility containing the gasifiable metal.

19. In a mold for casting metals, the mold having chambers surrounding the matrix of the mold. the chambers containing metal having low fusibility. the walls of the cavity impregnated with zinc and the metal of low fusibility containing zinc.

20. In a mold for casting metals, the mold having chambers substantially. surrounding the matrix of the mold, the chambers containing lead, the walls of" the molding cavity impregnated with a metal gasifiable below the temperature of the melting point of the metal cast, and the lead containing additional amounts of the gasifiable metal.

21. In ,a mold for casting materials, the mold having chambers substantially surrounding the matrix of the mold, the chambers containing lead and zinc, the walls of the cavity impregnated with zinc.

22. The process of casting fusible mate-rial in a mold which consists in maintaining the walls of the molding cavity at a high temperature by a heated metal of low fusibility located outside of the walls of the cavity, and introducing the material into the cavity.

23. The process of casting materials in a mold which consists in maintaining the walls of the molding cavity at a substantially uniform high temperature by a heated metal of low fusibility substantially surrounding the walls of the cavity, and introducing the material into the cavity.

24. The process of casting materials in a mold which consists in maintaining the walls of the molding cavity at a high temperature by a heated metal of low fusibilit-y and high conductivity, exterior to the cavity and introducing the material into the cavity.

25. The process of casting materials in a mold which consists in maintaining the walls of the molding cavity at a high temperature by a heated metal of low fusibility and high boiling point, exterior to the cavity and introducing the material into the cavity.

26. The process of casting materials in a mold which consists in maintaining the walls of the molding cavity at a high temperature by a heated metal of low fusibility and high vaporizing point, exterior to the cavity and introducing the material into the cavity.

27. The. process of casting ferrous metals in molds which consists in impregnating the molds with a metal gasifiable at a temresaoae in molds which consists in impregnating the walls of the cavity of the mold with zinc, surrounding the walls with heated lead, and inserting the molten ferrous metal into the molds.

30. The rocess of casting ferrous metals which consists in impregnating the walls of the cavity with zinc, surrounding the walls with a metal containing zinc, and inserting the molten ferrous metal into the molds.

31. The process of casting ferrous metals in molds which consists in forcing a metal gasifiable at a temperature below the melting point of the metal east through the wall of the mold by subjecting the said gasifiable metal to heat and pressure, and inserting the ferrous metal into the cavity of the mold.

32. The process of casting ferrous metals in molds which consists in forcing a metal gasifiable at a temperature below the melting point of the metal east through the wall of the mold by subjecting the said gasifiable metal to heat and its vapor pressure, and inserting the ferrous metal into the cavity of the mold.

In testimony whereof, I have hereunto signed my name to this specification.

ERT A. MYERS. 

